Passenger seat with seat back breakover assembly and method

ABSTRACT

A passenger seat is with a seat back breakover assembly for preventing movement of the seat back unit forwardly past an upright position during normal use and for permitting forward movement of the seat back past an upright position in response to a predetermined abnormal load applied in a forward direction. The breakover assembly includes a controlled deformation member having a bend in one end thereof and positioned intermediate one a section assembly module of the seat and the seat back unit. The bend of the deformation member captures therein an attachment member fixed to and movable forwardly and rearwardly in unison with the seat back unit. An end of the deformation member remote from the bend is restrained for restricted and controlled movement relative to the section assembly module. The deformation member has a resistance to deformation in response to a normal forwardly-applied force sufficient to prevent forward movement of the seat back unit beyond the upright position. The deformation member is deformable in response to an abnormal forwardly-applied force along its length whereby the bend in the deformation member is translated rearwardly along the length of the deformation member to thereby dissipate the abnormal force without damage to the seat back unit.

TECHNICAL FIELD AND BACKGROUND OF THE INVENTION

This invention relates to a passenger seat, or “seating unit”, such asan aircraft passenger seat, with a breakover assembly. By the term“breakover” is meant the ability of the seat back of the seating unit topivot forwardly past its normal upright position under predefinedcircumstances to a position where the seat back rests adjacent the seatbottom.

Aircraft passenger seats must be designed and constructed according togovernment regulations and aircraft manufacturer specifications.Virtually every aspect of seat design is thus constrained byrequirements imposed by safety, weight and expense considerations.Within these limits the seat must also be aesthetically pleasing,comfortable to the seat occupant, and functional for the seat occupantas well as airline maintenance, repair and cleaning crews.

Main cabin, or “coach” class seats are typically constructed with a seatbottom chassis formed from two or more leg modules and section assemblymodules joined together by several beam elements which connect the legmodules and section assembly modules in spaced-apart relation to eachother, and collectively form a ladder frame assembly. A seat bottom unitis mounted on the ladder frame assembly. The seat bottom unit is usuallystationary. A seat back unit is pivotally-mounted between two of thesection assembly modules so that the angle of the seat back unit can becontrolled for reasons of comfort, safety and passenger ingress andegress past the rear of the seat. Because of the relatively short pitchbetween rows of seats, the normal range of movement of the seat backunit is relatively small. The degree of rearward, recline movement isconstrained by the position of the rearward row of seats and therequirement to leave the passenger seated behind a particular seat withsufficient room to enter and exit his own and use the meal tray. Thedegree of forward movement of the seat back unit is limited to aposition where the passenger is in a forwardmost “upright” position fortake-off and landings, and for meal service.

Passenger seats are designed whereby the seat back unit will not movebeyond these positions under normal circumstances. However, provisionmust also be made for the abnormal situation where severe G-force loadsare directed against the seat back unit. In such cases, the seat backmust be allowed to “breakover” in a controlled manner in order tominimize damage to the seat and injury to a rear-seated passenger whomay be thrown against the seat back during an emergency event.

As used herein, “normal” load refers to those loads which are normallyapplied to the seat back during normal use, and includes loads imposedby passengers pushing or leaning on the seat back unit during ingressand egress, and minor rear impacts such as may occur during hardlandings or “short” stops upon landing. As used herein, “abnormal” loadrefers to any load in excess of a normal load and as specified ingovernment regulations or aircraft manufacturer specifications. Theserequirements are well-known to all aircraft seat manufacturers. Ingeneral, such abnormal loads may be in the range of 16 G's.

SUMMARY OF THE INVENTION

Therefore, it is an object of the invention to provide a passenger seatwith a breakover assembly which permits the seat back unit of the seatto “breakover” into a position against the seat bottom unit upon theoccurrence of a specified abnormal G-force load event.

It is another object of the invention to provide a passenger seat with abreakover assembly which reduces damage to the seat during applicationof an abnormal load.

It is another object of the invention to provide a passenger seat with abreakover assembly which reduces injury to a passenger seated aft of theseat.

It is another object of the invention to provide a passenger seat with abreakover assembly which can be quickly and easily replaced after anabnormal G-force event.

It is another object of the invention to provide a passenger seat with abreakover assembly which does not interfere with normal seat use andoperation.

These and other objects of the present invention are achieved in thepreferred embodiments disclosed below by providing a passenger seathaving a seat back breakover assembly, comprising a seat bottom chassisincluding a plurality of leg modules and a plurality of section assemblymodules. A plurality of beam elements carries the leg modules andsection assembly modules in spaced-apart relation to each other todefine a ladder frame assembly. A seat back unit is pivotally-mountedbetween two of the section assembly modules for permitting the angle ofthe seat back relative to the seat bottom chassis to be varied asdesired by the passenger. A recline unit is provided for controllingmovement of the seat back and locking the seat back in a desired reclineposition. A breakover assembly is provided for preventing movement ofthe seat back unit forwardly past an upright position during normal useand for permitting forward movement of the seat back past an uprightposition in response to a predetermined abnormal load applied in aforward direction. The breakover assembly includes a controlleddeformation member having a bend in one end thereof and positionedintermediate one of the section assembly modules and the seat back unit.The bend of the deformation member captures therein an attachment memberfixed to and movable forwardly and rearwardly in unison with the seatback unit. An end of the deformation member remote from the bend isrestrained for restricted and controlled movement relative to thesection assembly module. The deformation member has a resistance todeformation in response to a normal forwardly-applied force sufficientto prevent forward movement of the seat back unit beyond the uprightposition. The deformation member is deformable in response to anabnormal forwardly-applied force along its length whereby the bend inthe deformation member is translated rearwardly along the length of thedeformation member to thereby dissipate the abnormal force withoutdamage to the seat back unit.

According to one preferred embodiment of the invention, the controlleddeformation member comprises a steel wire.

According to another preferred embodiment of the invention, thedeformation member is restrained in a quadrant assemblystationarily-mounted on the section assembly module.

According to yet another preferred embodiment of the invention, thedeformation member has an enlarged head on the end thereof defining thebend, and further wherein the quadrant assembly includes an elongateslot therein for receiving the deformation member with an enlargedrecess communicating with the slot and receiving and capturing theenlarged head of the deformation member for locking the enlarged head ina fixed stationary position relative to the section assembly module.

According to yet another preferred embodiment of the invention, thequadrant includes a shear recess therein for receiving a pin with asacrificial, breakable bushing positioned thereon. The recess isdimensioned to allow the pin to pass out of the recess upon breakage ofthe bushing positioned thereon upon an initial phase of the abnormalforward movement of the seat back unit to provide initial resistance tothe forward movement of the seat back unit.

According to yet another preferred embodiment of the invention, thequadrant includes an outer surface for supporting thereon the metallicwire rearwardly of the bend therein, and a retainer bracket formaintaining the metallic wire against the outer surface of the quadrant.

According to yet another preferred embodiment of the invention, theattachment member is positioned in the bend of the wire and comprises aroller mounted on a pin fixed to the seat back unit.

According to yet another preferred embodiment of the invention, theinvention includes a fluid cylinder assembly pivotally-mounted by afirst end thereof to a section assembly module of the seat and by anopposite second end thereof to the seat back unit. The cylinder assemblyhas a longitudinally-extending axis extending in alignment with thelongitudinally-extending, generally vertical plane of the seat back. Anactuator is positioned astride and operatively connected to the fluidcylinder adjacent one or the other of the first and second ends thereof.An occupant-activated seat back recline control is provided formaintaining the seat back in a normally-locked condition relative to theseat bottom chassis for permitting the occupant to release thenormally-locked condition of the cylinder assembly by activating theseat back recline control to permit movement of the seat back to adesired position, and deactivating the seat back recline control to lockthe seat back in the desired position.

According to yet another preferred embodiment of the invention, theretainer bracket is carried by and is movable with the second end of thefluid cylinder assembly.

According to yet another preferred embodiment of the invention, apassenger seat having a seat back breakover assembly is provided, andcomprises a seat bottom chassis including a plurality of leg modules anda plurality of section assembly modules. A plurality of beam elementscarries the leg modules and section assembly modules in spaced-apartrelation to each other to define a ladder frame assembly. A seat backunit is pivotally-mounted between two of the section assembly modulesfor permitting the angle of the seat back relative to the seat bottomchassis to be varied as desired by the passenger. A recline unit isprovided for controlling movement of the seat back and locking the seatback in a desired recline position. A breakover assembly is provided formovement of the seat back unit forwardly past an upright position duringnormal use and for permitting forward movement of the seat back past anupright position in response to a predetermined abnormal load applied ina forward direction thereto. The breakover assembly includes an elongatesteel wire having a bend in one end thereof and positioned intermediateone of the section assembly modules and the seat back unit. The bend ofthe wire captures therein an roller fixed to and movable forwardly andrearwardly in unison with the seat back unit. An end of the wire remotefrom the bend is restrained for restricted and controlled movementrelative to the section assembly module. The wire has a resistance todeformation in response to a normal forwardly-applied force sufficientto prevent forward movement of the seat back unit beyond the uprightposition. The wire is deformable in response to an abnormalforwardly-applied force along its length whereby the bend in the wire istranslated rearwardly along the length of the wire to thereby dissipatethe abnormal force without damage to the seat back unit.

According to yet another preferred embodiment of the invention, the wireis restrained in a quadrant assembly stationarily-mounted on the sectionassembly module.

According to yet another preferred embodiment of the invention, the wirehas an enlarged head on the end thereof defining the bend. The quadrantassembly also includes an elongate slot for receiving the wire with anenlarged recess communicating with the slot and receiving and capturingthe enlarged head of the wire for locking the enlarged head in a fixedstationary position relative to the section assembly module.

According to yet another preferred embodiment of the invention, thequadrant includes a shear recess therein for receiving a pin with asacrificial, breakable bushing positioned thereon, the recessdimensioned to allow the pin to pass out of the recess upon breakage ofthe bushing positioned thereon upon an initial phase of the abnormalforward movement of the seat back unit to provide initial resistance tothe forward movement of the seat back unit.

According to yet another preferred embodiment of the invention, thequadrant includes an outer surface for supporting thereon the metallicwire rearwardly of the bend therein, and a retainer bracket formaintaining the metallic wire against the outer surface of the quadrant.

According to yet another preferred embodiment of the invention a fluidcylinder assembly is provided and is pivotally-mounted by a first endthereof to a section assembly module of the seat and by an oppositesecond end thereof to the seat back unit. The cylinder assembly has alongitudinally-extending axis extending in alignment with thelongitudinally-extending, generally vertical plane of the seat back. Anactuator is positioned astride and operatively connected to the fluidcylinder adjacent one or the other of the first and second ends thereof.An occupant-activated seat back recline control is provided formaintaining the seat back in a normally-locked condition relative to theseat bottom chassis to permit the occupant to release thenormally-locked condition of the cylinder assembly by activating theseat back recline control to thus permit movement of the seat back to adesired position and deactivating the seat back recline control to lockthe seat back in the desired position.

An embodiment of the method according to the invention comprisespreventing movement of a reclinable seat back unit of a passenger seatforwardly past an upright position during normal use and permittingforward movement of the seat back past an upright position into abreakover position in response to a predetermined abnormal load appliedin a forward direction thereto. The method includes the steps ofproviding a controlled deformation member having a bend in one endthereof, positioning the deformation member intermediate a stationarysection assembly module of the passenger seat and the seat back unitcarried by the section assembly module, and capturing in the bend of thedeformation member an attachment member fixed to and movable forwardlyand rearwardly in unison with the seat back unit. An end of thedeformation member remote from the bend is restrained for restricted andcontrolled movement relative to the section assembly module. Thedeformation member has a resistance to deformation in response to anormal forwardly-applied force sufficient to prevent forward movement ofthe seat back unit beyond the upright position. The deformation memberhas characteristics permitting deformation in response to an abnormalforwardly-applied force along its length whereby the bend in thedeformation member is translated rearwardly along the length of thedeformation member to thereby dissipate the abnormal force withoutdamage to the seat back unit.

According to yet another preferred embodiment of the invention, the stepof providing a deformation member comprises the step of providing asteel wire.

According to yet another preferred embodiment of the invention, thesteel wire is a 0.235 inch 1018 grade wire.

According to yet another preferred embodiment of the invention, anattachment member is captured in the bend of the deformation member, andis fixed to and movable forwardly and rearwardly in unison with the seatback unit comprises the step of capturing a roller.

According to yet another preferred embodiment of the invention, themethod includes the step of capturing an enlarged head formed on thebend end of the deformation member in a quadrant fixed to the sectionassembly module for securing the enlarged head in a stationary positionrelative to the section assembly module during deformation of thedeformation member.

BRIEF DESCRIPTION OF THE DRAWINGS

Some of the objects of the invention have been set forth above. Otherobjects and advantages of the invention will appear as the inventionproceeds when taken in conjunction with the following drawings, inwhich:

FIG. 1 is a front perspective view of a seat set of aircraft passengerseats according to an embodiment of the present invention;

FIG. 2 is a rear perspective view of the seat set shown in FIG. 1;

FIG. 3 is an end perspective view of the seat set shown in FIG. 1;

FIG. 4 is fragmentary perspective view of the seat set with parts,including the upholstery and cushions, removed for clarity;

FIG. 5 is a side elevation of the frame of the aisle seat shown in FIG.1;

FIG. 6 is a fragmentary exploded view of a seat back recline lockingassembly;

FIG. 7 is a fragmentary exploded view of further components of the seatback recline locking assembly of FIG. 6;

FIG. 8 is an exploded view of a leg module and joint clamp assemblyaccording to an embodiment of the invention;

FIGS. 9-11 illustrate different spacings which are possible using theleg module and joint clamp assembly shown in FIG. 8;

FIGS. 12 and 13 are exploded perspective views of a seat back breakoverassembly;

FIGS. 13A, 13B and 13C are fragmentary enlarged side-elevationsequential views of the seat breakover assembly during a breakoverevent;

FIG. 14 is a overall, exploded perspective view of the breakoverassembly in relation to the seat back;

FIG. 15 is an exploded view of a meal tray assembly according to anembodiment of the invention;

FIG. 16 is a perspective view of the meal tray assembly shown in FIG. 15in the stowed position;

FIG. 17 is an exploded view of a meal tray assembly according to asecond embodiment of the invention;

FIG. 18 is a perspective view of the meal tray assembly shown in FIG. 17in the use position; and

FIG. 19 is a perspective view of the meal tray assembly shown in FIG. 17in the stowed position.

DESCRIPTION OF THE PREFERRED EMBODIMENT AND BEST MODE SEAT ASSEMBLYOVERVIEW

Referring now specifically to the drawings, an aircraft passenger seatset according to the present invention is illustrated in FIGS. 1, 2 and3 and shown generally at reference numeral 10. In the particularembodiment shown in FIGS. 1, 2 and 3, the seat set 10 is comprised ofthree adjacent seats, an aisle seat 11, a center seat 12 and a windowseat 13. The seat set 10 is supported on a pair of leg modules 14 and15, and includes a baggage guard rail 16. The seats 11, 12 and 13 areprovided with arm rests 18, 19, 20 and 21. The seats 11, 12 and 13include seat bottoms 22, 23 and 24, respectively, and seat backs 25, 26and 27, respectively.

The internal structure of the seat set is shown in FIG. 4, with variousparts eliminated for clarity. As is shown, the seat set 10 is supportedon and thus shares the two leg modules 14 and 15. The leg modules 14 and15 carry a set of four laterally-extending beam elements 35, 36, 37 and38 on which are mounted four section assembly modules 40, 41, 42 and 43.The leg modules 14, 15; beam elements 35, 36, 37 and 38; and the sectionassembly modules 40, 41, 42 and 43 tie together the components in amanner necessary to form a seat set 10 having significant structuralintegrity within passenger comfort, fuselage size and governmentregulation requirements. The underlying structure defined by leg modules14, 15; beam elements 35, 36, 37 and 38; and the section assemblymodules 40, 41, 42 and 43 is referred to as a “ladder frame assembly”and is indicated at reference numeral 50 in FIGS. 4 and 5. The ladderframe assembly 50 carries seat back pans 26A, 27A, see FIG. 4, and seatback pan 25A, see FIG. 5.

Of course, the seats according to the present invention can beintegrated together to form seat sets of different lengths, spacings,and numbers of seats. Whether one, two, three or more seats, each seatset 10 will include at least two leg modules, such as leg modules 14 and15. Thus, when a seat is referred to as having a pair or a plurality ofleg modules, it is understood that at least two leg modules arerequired, but that the two leg modules may not necessarily be onopposing sides of any particular seat. For example, in FIGS. 1-5, threeseats 11, 12 and 13 are each supported on two leg modules 14, 15. Thus,seat 11 is supported on two leg modules 14, 15, just as are seats 12 and13, whether the seat set 10 is considered a “seat” or the three seats11, 12 and 13 are considered “seats”, in either case they are supportedby a plurality of legs.

LOW PROFILE SEAT BACK RECLINE LOCKING ASSEMBLY

Referring now to FIGS. 6 and 7, a low profile seat back recline lockingassembly is shown. A hydraulic cylinder 60 interconnects the sectionassembly module 41 and the seat back pan 25A. A control button, notshown, on the arm rest 19 can be depressed by the seat occupant to varythe recline angle of the seat back 26 relative to the seat bottom 23.The control button is connected to a control cable, not shown, whichconnects to the actuator 61 residing on top of the cylinder 60. When thecontrol button is depressed, the actuator 61 unlocks the cylinder 60.Backward pressure on the seat back pan 25A allows the seat back pan 25Ato recline. Release of back pressure on the seat back pan 25A by theseat occupant allows the seat back pan 25A to move forwardly to a moreupright position. Release of the control button locks the seat back 25in the current position.

The cylinder 60 is mounted for pivotal movement to the section assemblymodule by an offset pivot shaft 62 by a lower cylinder pivot bushing 63and to the seat back pan 25A by a pair of upper cylinder pivot bushings64, 65 between which fits a pivot bushing, not shown, residing behindthe lower extent of the seat back pan 25A. The upper cylinder pivotbushings 64, 65 are locked in place by a lock pin 68, designed to beremovable without tools.

The pivot shaft 62 is locked to the section assembly module 41 by apear-shaped spacer collar 70 having a bore 71 into which the pivot shaft62 extends. The spacer collar 70 is connected to the section assemblymodule 41 by a screw 72 which is threaded into a matingly threaded screwhole 73 in the small end of the spacer collar 70.

Note that the spacer collar 70 fits against a stepped surface portion ofthe section assembly module 41. The stepped surface portion includes afirst portion 75 which is flush with the surrounding surface of thesection assembly module 41 and a second portion 76 which is recessedbelow the surrounding surface of the section assembly module 41. Thepivot shaft fits into a bore 78 in the section assembly module 41, andthe screw 72 threads into a matingly threaded hole 79.

Thus, in order to lock the pivot shaft 62 against movement relative tothe section assembly module 41, the screw 72 is tightened to the pointwhere the smaller end of the spacer collar 70 is drawn inwardly into therecessed portion 76 of the section assembly module underlying the spacercollar 70. This tilting movement creates a misalignment of the axis ofthe spacer collar 70 relative to the axis of the pivot shaft 62, thuslocking the pivot shaft 62 against both axial and rotational movementrelative to the section assembly module 41. As the seat back pan 25Amoves, the cylinder 60 pivots about the pivot shaft 62.

Similarly, the seat back pivot shaft 80 is mounted in a pivot bushing 81on the seat back pan 25A and in a bore 82 in the section assembly module41. The seat back pivot shaft 80 is locked to the section assemblymodule 41 by a spacer collar 84. In the same manner as described above,the spacer collar 84 sits over a stepped portion of the surface of thesection assembly module 41, so that when the screw 85 is tightened, thesmall end of the spacer collar 84 is misaligned, locking the seat backpivot shaft 80 in a fixed position relative to the section assemblymodule 41.

The spacer collars 70 and 84 are preferably manufactured from extrusionand thus can be easily made in any desired thickness.

The seat back pivot shaft 80 is attached to the pivot bushing by afastener 87. A screw 88 is threaded into the fastener 87, which includesa misaligned portion 89. As the screw 88 is tightened, the misalignedportion 89 becomes progressively more misaligned, securing the seat backpivot shaft 80 to the pivot bushing 81 of the seat back pan 25A.

As is shown in FIG. 7, beam elements 35 and 36 carry the sectionassembly module 41, also as shown in FIG. 4, together with the beamelements 37 and 38.

The cylinder 60 is very compact—approximately 5 inches betweenattachment points, and has a ½ inch stoke. By locating the actuator 61astride the cylinder 60, the overall length is further reduced. Thisshorter length allows the cylinder 60 to be located in a nearly verticalposition to one side of and behind the seat occupant. The seat bottompan therefore has a clean appearance without local protuberances. As aresult, the bottom cushion can be thinner, less complex, morecomfortable and lighter than those in current use. Recline of the seatback 26 is unaffected, and is completely transparent to the seatoccupant.

SEAT FRAME CONSTRUCTION

Referring now to FIG. 8, leg module 14 is described in further detail.Leg module 14 includes a rear floor track fitting 90 by which the seatset 10 is attached to a track extending along the fuselage deck fromfront to rear, a floor tie assembly 91, a front leg 92, a front trackfitting 93, and a diagonal leg tie 94. A pair of joint clamps 96, 98 areprovided and comprise an annular collar element 96A, 98A, respectively,which receive the beam elements 37, 36, and attachment elements 96B,98B, respectively, by which the joint clamps 96, 98 are attached to theleg module 14.

The joint clamps 96, 98 are secured by screws 99 to the top of the frontleg 92 and the diagonal leg tie 94, respectively. The joint clamps 96,98 include axially-extending splits 96C, 98C, respectively, which permitthe collar elements 96B, 98B to be spread sufficiently to permitinsertion of the beam elements 37, 36. Screws 100 permit the collarelements 96B, 98B to be tightened for locking the beam elements 37, 36in place in a predetermined position, and loosened for permitting thebeam elements 37, 36 to the removed from or shifted axially within thecollar elements 96B, 98B.

As shown in FIG. 4, the section assembly modules 41 and 42 are mountedto the beam elements 37, 36 in an offset position relative to the jointclamps 96, 98 and form the ladder frame assembly 50.

Referring now to FIGS. 9, 10 and 11, the manner in which the jointclamps 96, 98 may be used to vary seat spacing is illustrated. As notedabove, spacing between parallel sets of floor tracks is generally fixed,so that the need to have seats with varying spacing in prior artconstructions has been accommodated by having differently-constructedleg modules with various offsets to the left or right of the centerlineof the leg module. By using the joint clamps 96, 98, seat spacing isvaried using the same components, avoiding the need to have a number ofdifferently-constructed leg modules and components. For example, in FIG.9 the joint clamps 96, 98 are positioned on the right side of the legmodules 14, 15. The location of the collars 96A, 98A permit the sectionassembly modules 41, 42 to be positioned in vertical alignment with orto the left of the leg modules 14, 15.

In FIG. 10 the joint clamps 96, 98 are positioned on the left side ofthe leg modules 14, 15, permitting the section assembly modules 41, 42to be positioned in vertical alignment with or to the right of the legmodules 14, 15.

In FIG. 11 the joint clamps 96, 98 are positioned in board of the legmodules 14, 15, permitting the section assembly modules 41, 42 to bepositioned in vertical alignment with or outboard of the leg modules 14,15. Even though not shown, it is also apparent that the joint clamps canbe both positioned outboard of the leg modules 14, 15, permitting thesection assembly modules 41, 42 to be positioned in vertical alignmentwith in board of the leg modules 14, 15. The attachments are notpermanent, so that modifications to the seat spacing requirements can bequickly and easily accomplished.

SEAT BACK BREAKOVER ASSEMBLY

Referring now to FIGS. 12, 13, 13A-C and 14, a breakover assembly for apassenger seat such as the passenger seat 11 is shown. The breakoverassembly 100 is intended to normally prevent the seat back 25, see FIG.5, from pivoting forward past an upright position towards the seatbottom 22, while allowing this movement if struck with a sufficientlyhard forwardly-directed force, such as might occur if hit from the rearby an occupant seated directly behind the seat. The purpose of thebreakover assembly is to prevent damage to the seat 11 resulting from asevere rear impact and to at least reduce injury to an occupant thrownagainst the rear of the seat back by allowing the seat back to moveforwardly in a controlled manner.

In general, this is effected by utilizing a bent steel wire to resistimpact up to a certain predetermined load, and then absorb the energy byforcing the bend in the wire rearwardly relative to the wire, forwardlyrelative to the seat, and giving off excess energy in the form of heat.

Specifically, a bent steel wire 101 as is shown in the simplified viewof FIG. 12 is captured by a retainer bracket 102. The steel wire is a.235 inch 1018 grade wire. An energy-absorbing roller 103 and bushing103A are positioned inside the bend of the steel wire 101. The roller103 is captured in holes 105A and 106A in back supports 105, 106,respectively and thus must move in unison with the back supports 105,106. The bushing 103A resides in lateral alignment with the steel wire101 inside the bend.

A shear pin 104 carrying a shear bushing 1 04A thereon is captured inholes 105B and 106B in back supports 105, 105, respectively. The shearbushing 104A is captured in an annular recess 107 in a quadrant member108. The steel wire 101 fits around the back side 108 of the quadrantmember 108, with the forward portion of the wire 101 positioned in theelongate slot 109. The forward portion of the wire 101 is retained inslot 109 by an enlarged head 101A which fits within an annular recess atthe end of the slot 109. See FIG. 13.

The entire seat back 25 pivots on the pivot bushing 112 on which theback supports 105, 106 and quadrant 108 are positioned. See FIG. 14.Other components shown are illustrated and described above.

In operation, an abnormal force, for example, the impact of a passengeron the rear of the seat during a 16 g event will cause the seat back 25to move forward while the quadrant 108 remains stationary. The shearbushing 104A fits snugly within the recess 107 and thus quickly breaks.The shear bushing 104A is designed to break upon impact of between180-220 pounds on the top of the seat back 25. See FIGS. 13A, 13B. Thewidth of the shear bushing 104A can be varied, and in doing so theamount of force required to break the shear bushing 104A can be varied.The wire 101 is protected from any load until the shear bushing 104Abreaks.

As the shear bushing 104A breaks, the seat back 25 continues forward,bringing the bushing 103A up against the back of the inside of the bendin the wire 101. As the seat back 25 continues forward, the bushing 103Acontinues forward, and the wire 101 is pulled around the bushing 103A,moving the position of the bend. See FIG. 13C. Energy is absorbed in twoways, movement of the position of the bend along the length of the wire101 and heat released as the wire 101 thus bent.

Wire 101 is designed to begin movement at 150 pounds of force, andpermits the seat back 25 to move through a maximum arc of 70 degrees.The combined use of the sacrificial bushing 104A and the wire 101controls the movement of the seat back 25 in such a manner thatsurvivability of the passenger is improved at an impact force as low as1G. The seat back 25 can be returned to its normal position by pushingit rearward using less than a 35 lbs force.

When the seat back must be moved forward for maintenance or cleaning,the lock pin 68 may be removed, disconnecting the hydraulic seat reclinecylinder 60 from the retainer bracket 102 and the seat back 25. In thisconfiguration the seat back 25 may be moved forward to the breakoverposition without interfering with the quadrant 108.

Meal Tray Assembly—Preferred Embodiment

Referring now to FIG. 15, a meal tray assembly 120 according a preferredembodiment of the invention is illustrated. The meal tray assemblyincludes a pair of laterally spaced-apart latch plates 121, 122connected to the back surface of the seat back pan 25A of passenger seat11 directly above a meal tray stowage position. The latch plates 121,122 include inwardly-facing pin retention recesses 121A, 122A,respectively. The dress cover of the seat back 25 is around the latchplates 121, 122 so as not to interfere with the latch plates 121, 122when the dress cover is removed for cleaning or replacement.

A cross-member 124 is positioned laterally across the surface of theseat back pan 25A and releasably locked to the seat back pan 25A by apair of locking pins 125, 126, which are mounted in recesses, not shown,in the back side of the cross-member 124 by a pair of cover plates 128,129. The cross-member 124 is positioned over the dress cover. Thelocking pins 125, 126 are biased in the locked position by springs 131,132. When the cross-member 124 is placed against the back of the seatback pan 25A and over the latch plates 121, 122, the locking pins 125,126 extend into the retention recesses 121A, 122A and lock thecross-member 124 to the back of the seat back pan 25A.

The cross-member 124 is contoured to define a central recess 135. Arotatable “barn door” latching member 137 is positioned within therecess 135 and is movable between an extended position with the latchingmember 137 extending downwardly from the cross-member 124 intointerfering relation with a top edge 139 of a meal tray 140, and aretracted position with the latching member 137 extending laterally toone side within the recess 135 in non-interfering relation with the topedge 139 of the meal tray 140. The meal tray 140 also includes a recess141 which communicates with the top edge 139 of the meal tray 140. Therecess 135 in the cross-member 124 and the recess 141 in the meal tray140 collectively form a recess within which the latching member 137resides, and thus prevents inadvertent impact from passing passengerswhich could cause deployment of the meal tray 140.

The locking pins 125, 126 are manually operable by downwardly-extendingfingers 125A, 126 from the lower side of the cross-member 124 when themeal tray 140 is in its deployed position.

Installation is accomplished without tools. Repairs and part replacementmay be made without tools and without removing the dress cover from theseat back 25.

Meal Tray Assembly—Alternative Embodiment

Referring now to FIGS. 17, 18 and 19, an alternative embodiment mealtray assembly 150 is shown. A meal tray 151 is mounted for movementbetween a stowage position flush against the back side of a seat backpan 25A, FIG. 19, and a lowered, horizontal use position, FIG. 18. Anelongate latch access port 153 extends through the meal tray 151 nearits top edge. Note that the latch access port is “subflush” to thebottom surface of the meal tray 151, and is surrounded by a recess 154.

A latch mounting plate 155 is secured to the back side of the seat backpan 25A, to which is mounted an annular detent plate 157. Detent plate157 includes four 90 degree detent dimples 157A molded into the face. Anelongate latch 160 is carried by the detent plate 157 by a pin assembly158 and is rotatable between a release position, shown in FIG. 18, wherethe elongate latch 160 may be aligned with and extended through theelongate latch access port 153 for permitting movement of the meal tray151 to and from the stowage position and the use position. When the mealtray 151 has been moved to the stowage position with the latch 160extending though the latch access port 153, the latch 160 is rotated ineither the clockwise or counterclockwise direction 90 degrees. The latch160 overlaps the edge of the latch access port 153 and is caught on theedge of the meal tray 151 surrounding the latch access port 153, lockingthe meal tray 151 in the stowage position.

To release the meal tray 151 and allow it to be moved to the useposition, the latch 160 is rotated a further 90 degrees in eitherdirection and into alignment with the lengthwise axis of the latchaccess port 153. In this position, the meal tray 151 may be lowered pastthe latch 160 and into the use position.

Because the latch 160 captures the meal tray 151 through the latchaccess port 153, inadvertent disengagement of the meal tray 151 by forceapplied in any direction is prevented, in contrast with current “barndoor” latches. In addition, the recess 154 around the latch access port153 prevents inadvertent rotation of the latch 160 and deployment of themeal tray 151 to the use position, as might otherwise occur when apassenger brushes against the tray while moving to or from his or herown seat.

A passenger seat with a breakover assembly is described above. Variousdetails of the invention may be changed without departing from itsscope. Furthermore, the foregoing description of the preferredembodiment of the invention and the best mode for practicing theinvention are provided for the purpose of illustration only and not forthe purpose of limitation—the invention being defined by the claims.

I claim:
 1. A passenger seat having a seat back breakover assembly,comprising: (a) a seat bottom chassis including a plurality of legmodules and a plurality of section assembly modules; (b) a plurality ofbeam elements carrying said leg modules and section assembly modules inspaced-apart relation to each other to define a ladder frame assembly;(c) a seat back unit pivotally-mounted between two of the sectionassembly modules for permitting the angle of the seat back relative tothe seat bottom chassis to be varied as desired by the passenger; (d) arecline unit for controlling movement of the seat back and locking theseat back in a desired recline position; and (e) a breakover assemblyfor preventing movement of the seat back unit forwardly past an uprightposition during normal use and permitting forward movement of the seatback past an upright position in response to a predetermined abnormalload applied in a forward direction thereto, and comprising: (a) acontrolled deformation member having a bend in one end thereof andpositioned intermediate one of said section assembly modules and saidseat back unit; (b) the bend of said deformation member capturingtherein an attachment member fixed to and movable forwardly andrearwardly in unison with the seat back unit; (c) an end of thedeformation member remote from the bend being restrained for restrictedand controlled movement relative to the section assembly module; (d)said deformation member having a resistance to deformation in responseto a normal forwardly-applied force sufficient to prevent forwardmovement of the seat back unit beyond the upright position; and (e) saiddeformation member being deformable in response to an abnormalforwardly-applied force along its length whereby the bend in thedeformation member is translated rearwardly along the length of thedeformation member to thereby dissipate the abnormal force withoutdamage to the seat back unit.
 2. A passenger seat according to claim 1,wherein said controlled deformation member comprises a steel wire.
 3. Apassenger seat according to claim 2, wherein said deformation member isrestrained in a quadrant assembly stationarily-mounted on said sectionassembly module.
 4. A passenger seat according to claim 3, wherein saiddeformation member has an enlarged head on the end thereof defining thebend, and further wherein the quadrant assembly includes an elongateslot therein for receiving the deformation member with an enlargedrecess communicating with the slot and receiving and capturing theenlarged head of the deformation member for locking the enlarged head ina fixed stationary position relative to the section assembly module. 5.A passenger seat according to claim 4, wherein said quadrant assemblyincludes a shear recess therein for receiving a pin with a sacrificial,breakable bushing positioned thereon, said recess dimensioned to allowthe pin to pass out of the recess upon breakage of the bushingpositioned thereon upon an initial phase of the abnormal forwardmovement of the seat back unit to provide initial resistance to theforward movement of the seat back unit.
 6. A passenger seat according toclaim 5, wherein said quadrant assembly includes an outer surface forsupporting thereon the metallic wire rearwardly of the bend therein, anda retainer bracket for maintaining the metallic wire against the outersurface of the quadrant assembly.
 7. A passenger seat according to claim6, and including: (a) a fluid cylinder assembly pivotally-mounted by afirst end thereof to a section assembly module of the seat and by anopposite second end thereof to the seat back unit, the cylinder assemblyhaving a longitudinally-extending axis extending in alignment with thelongitudinally-extending, generally vertical plane of the seat back; (b)an actuator positioned astride and operatively connected to the fluidcylinder adjacent one or the other of the first and second ends thereof;and (c) an occupant-activated seat back recline control for maintainingthe seat back in a normally-locked condition relative to the seat bottomchassis and for permitting the occupant to release the normally-lockedcondition of the cylinder assembly by activating the seat back reclinecontrol to thus permit movement of the seat back to a desired positionand deactivating the seat back recline control to lock the seat back inthe desired position.
 8. A passenger seat according to claim 7, whereinsaid retainer bracket is carried by and is movable with the second endof the fluid cylinder assembly.
 9. A passenger seat according to claim2, wherein said attachment member positioned in the bend of the wirecomprises a roller mounted on a pin fixed to the seat back unit.
 10. Apassenger seat having a seat back breakover assembly, comprising: (a) aseat bottom chassis including a plurality of leg modules and a pluralityof section assembly modules; (b) a plurality of beam elements carryingsaid leg modules and section assembly modules in spaced-apart relationto each other to define a ladder frame assembly; (c) a seat back unitpivotally-mounted between two of the section assembly modules forpermitting the angle of the seat back relative to the seat bottomchassis to be varied as desired by the passenger; (d) a recline unit forcontrolling movement of the seat back and locking the seat back in adesired recline position; and (e) a breakover assembly for preventingmovement of the seat back unit forwardly past an upright position duringnormal use and permitting forward movement of the seat back past anupright position in response to a predetermined abnormal load applied ina forward direction thereto, and comprising: (i) an elongate steel wirehaving a bend in one end thereof and positioned intermediate one of saidsection assembly modules and said seat back unit; (ii) the bend of saidwire capturing therein a roller fixed to and movable forwardly andrearwardly in unison with the seat back unit; (iii) an end of the wireremote from the bend being restrained for restricted and controlledmovement relative to the section assembly module (iv) said wire having aresistance to deformation in response to a normal forwardly-appliedforce sufficient to prevent forward movement of the seat back unitbeyond the upright position; and (v) said wire being deformable inresponse to an abnormal forwardly-applied force along Its length wherebythe bend in the wire is translated rearwardly along the length of thewire to thereby dissipate the abnormal force without damage to the seatback unit.
 11. A passenger seat according to claim 10, wherein said wireis restrained in a quadrant assembly stationarily-mounted on saidsection assembly module.
 12. A passenger seat according to claim 11,wherein said wire has an enlarged head on the end thereof defining thebend, and further wherein the quadrant assembly includes an elongateslot therein for receiving the wire with an enlarged recesscommunicating with the slot and receiving and capturing the enlargedhead of the wire for locking the enlarged head in a fixed stationaryposition relative to the section assembly module.
 13. A passenger seataccording to claim 12, wherein said quadrant assembly includes a shearrecess therein for receiving a pin with a sacrificial, breakable bushingpositioned thereon, said recess dimensioned to allow the pin to pass outof the recess upon breakage of the bushing positioned thereon upon aninitial phase of the abnormal forward movement of the seat back unit toprovide initial resistance to the forward movement of the seat backunit.
 14. A passenger seat according to claim 13, wherein said quadrantassembly includes an outer surface for supporting thereon the metallicwire rearwardly of the bend therein, and a retainer bracket formaintaining the metallic wire against the outer surface of the quadrantassembly.
 15. A passenger seat according to claim 14, and including: (a)a fluid cylinder assembly pivotally-mounted by a first end thereof to asection assembly module of the seat and by an opposite second endthereof to the seat back unit, the cylinder assembly having alongitudinally-extending axis extending in alignment with thelongitudinally-extending, generally vertical plane of the seat back; (b)an actuator positioned astride and operatively connected to the fluidcylinder adjacent one or the other of the first and second ends thereof;and (c) an occupant-activated seat back recline control for maintainingthe seat back in a normally-locked condition relative to the seat bottomchassis and for permitting the occupant to release the normally-lockedcondition of the cylinder assembly by activating the seat back reclinecontrol to thus permit movement of the seat back to a desired positionand deactivating the seat back recline control to lock the seat back inthe desired position.
 16. A method of preventing movement of areclinable seat back unit of a passenger seat forwardly past an uprightposition during normal use and permitting forward movement of the seatback past an upright position into a breakover position in response to apredetermined abnormal load applied in a forward direction thereto, andcomprising the steps of: (a) providing a controlled deformation memberhaving a bend in one end thereof; (b) positioning said deformationmember intermediate a stationary section assembly module of thepassenger seat and said seat back unit carried by said section assemblymodule; (c) capturing in the bend of the deformation member anattachment member fixed to and movable forwardly and rearwardly inunison with the seat back unit; (d) restraining an end of thedeformation member remote from the bend for restricted and controlledmovement relative to the section assembly module; (e) providing saiddeformation member with a resistance to deformation in response to anormal forwardly-applied force sufficient to prevent forward movement ofthe seat back unit beyond the upright position; and (f) providing saiddeformation member with characteristics permitting deformation inresponse to an abnormal forwardly-applied force along its length wherebythe bend in the deformation member is translated rearwardly along thelength of the deformation member to thereby dissipate the abnormal forcewithout damage to the seat back unit.
 17. A method according to claim16, wherein the step of providing a deformation member comprises thestep of providing a steel wire.
 18. A method according to claim 17,wherein the steel wire is a 0.235 inch 1018 grade wire.
 19. A methodaccording to claim 16, wherein the step of capturing in the bend of thedeformation member an attachment member fixed to and movable forwardlyand rearwardly in unison with the seat back unit comprises the step ofcapturing a roller.
 20. A method according to claim 16, and includingthe step of capturing an enlarged head formed on the bend end of thedeformation member in a quadrant fixed to said section assembly modulefor securing the enlarged head in a stationary position relative to thesection assembly module during deformation of the deformation member.